Using a variety of preparative techniques for electron microscopy, we have obtained evidence for the disposition of actin and myosin in vertebrate smooth muscle. All longitudinal myofilaments seen in sections appear to be actin. Previous reports of two types of longitudinal filaments in sections are accounted for by technical factors, and by differentiated areas of opacity along individual fila...

Caffeine is sometimes used in cell physiological studies to release internally stored Ca(2+). We obtained evidence that caffeine may also act through a different mechanism that has not been previously described and sought to examine this in greater detail. We ruled out a role for phosphodiesterase (PDE) inhibition, since the effect was 1) not reversed by inhibiting PKA or adenylate cyclase; 2) ...

In most forms of renal injury, even those due to a primary glomerular process, the extent of tubulointerstitial scarring is a critical determinant of renal functional reserve and prognosis. Yet, little is known about the functional characteristics of the interstitial cells that mediate the processes of chronic tubulointerstitial injury. In this study, tissues from normal kidney (N = 7), from ne...

To determine whether chronic treatment with enalapril initiated early in life prevents glomerular injury secondary to normal aging, CF1 mice received enalapril (20 mg/L, n=10) or nifedipine (40 mg/L, n=10) in their drinking water from the time of weaning to 12 months of life. Control mice (n=10) received tap water ad libitum. Immunocytochemical detection of renin confirmed that angiotensin-conv...

1. We have investigated the ability of bovine brain S.100, and of three related proteins from sheep aorta smooth muscle, to confer Ca(2+)-sensitivity on thin filaments reconstituted from smooth-muscle actin, tropomyosin and caldesmon. 2. At 37 degrees C in pH 7.0 buffer containing 120 mM-KCl, approximately stoichiometric amounts of S.100 reversed caldesmon's inhibition of the activation of myos...

Tropomyosin (Tm) is known to be an important gatekeeper of actin function. Tm isoforms are encoded by four genes, and each gene produces several variants by alternative splicing, which have been proposed to play roles in motility, proliferation, and apoptosis. Smooth muscle studies have focused on gizzard smooth muscle, where a heterodimer of Tm from the α-gene (Tmsm-α) and from the β-gene (Tms...

Smooth muscle contraction differs somewhat from skeletal muscle. Ca is involved in the initiation of contraction as it is in skeletal muscle. However, the myosin in smooth muscle must be phosphorylated for activation of the myosin ATPase. Phosphorylation and dephosphorylation of myosin also occurs in skeletal muscle, but phosphorylation is not necessary for activation of the ATPase. In smooth m...

European Journal of ImmunologyVolume 53, Issue 9 2370091 Cover PictureFree Access Story: Eur. J. Immunol. 9'23 First published: 07 September 2023 https://doi.org/10.1002/eji.202370091AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text full-text accessPlease review our Terms and Conditions Use check box below share version article.I...

Using a variety of preparative techniques for electron microscopy, we have obtained evidence for the disposition of actin and myosin in vertebrate smooth muscle. All longitudinal myofilaments seen in sections appear to be actin. Previous reports of two types of longitudinal filaments in sections are accounted for by technical factors, and by differentiated areas of opacity along individual fila...

introduction: we did this study because there were a few studies about aorto-branch junction. methods: four light microscope and electron microscope study, the abdominal aorta, renal artery, and the adjoining right and left renal arteries were dissected out from 4 neonate dogs. results: based on the results, there is only one cell type in the tunica intima of endothelium in both arteries. in ab...